In systems such as home automation networks, devices (nodes) can communicate with each other using a networking protocol. For security and privacy reasons, this communication is often encrypted. When individual devices in the network do not have sufficiently powerful processors or large enough memory capacities, certain cryptographic protocols cannot be used. For example, in some home automation networks, it may be impractical to implement a processor-intensive cryptographic protocol, such as public key cryptography. Another method of securing communications can include symmetric keys and symmetric cryptographic protocols.